ORA-03134: Connections to this server version are no longer supported.

I got ” ORA-03134: Connections to this server version are no longer supported. ”  error in Oracle database.

ORA-03134: Connections to this server version are no longer supported.

Details of error are as follows.

ORA-03134: Connections to this server version are no longer supported.

Cause: An attempt was made to connect to an Oracle server of older version.

Action: Please refer to documentation for more details.

Connections to this server version are no longer supported.

This ORA-03134 error is related with the attempt was made to connect to an Oracle server of older version.

Please refer to documentation for more details.

Change your sqlnet.ora file like below. Add these two lines to the sqlnet.ora

SQLNET.ALLOWED_LOGON_VERSION_SERVER=8
SQLNET.ALLOWED_LOGON_VERSION_CLIENT=8

[oracle@MehmetSalih ~]$ ps -ef | grep smon
oracle 25167 17807 0 11:56 pts/0 00:00:00 grep --color=auto smon
oracle 28385 1 0 10:31 ? 00:00:00 ora_smon_DEVECI19C
[oracle@MehmetSalih ~]$
[oracle@MehmetSalih ~]$
[oracle@MehmetSalih ~]$ cd $ORACLE_HOME
[oracle@MehmetSalih install]$ cd network/admin/
[oracle@MehmetSalih admin]$


[oracle@MehmetSalih admin]$ cat sqlnet.ora
# sqlnet.ora Network Configuration File: /oradata/install/network/admin/sqlnet.ora
# Generated by Oracle configuration tools.

NAMES.DIRECTORY_PATH= (TNSNAMES, EZCONNECT)


SQLNET.ALLOWED_LOGON_VERSION_SERVER=8
SQLNET.ALLOWED_LOGON_VERSION_CLIENT=8

If you change sqlnet.ora file which is under the $ORACLE_HOME/network/admin then reload your listener like below. And try to connect again.

[oracle@MehmetSalih admin]$ lsnrctl reload

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